Hi! > Your assumption that the same file descriptor is being re-opened is > wrong! > The file descriptor retrieved via /proc is a new one. It is not the > same as the > initial read-only. True, we were just being sloppy with the words. But it does not matter one iota. > As Martin Rex already explained yesterday, /proc is all virtual. > The item referred as fd in /proc is not a real file descriptor and as > of that, that 'not-tfor-real file descriptor' is also not re-opend > and so does > not become read-write. True. > Imagen: > - a house surrounded with a fence with all doors unlocked (file with > perm 0666) > - a drive-way leads to the gate in the fence and the gate is > unlocked (dir with perms 777) > - next we put a lock on the gate and don't give guest the key (dir > with perms 700) > - guest cannot access the house because he can't pass the gate > - now we take an airplane and parachute guest straight into the > perimeter of the fence (/proc access) > - guest can access the house (write the file), because the house has > all doors unlocked Exactly, and I'm saying that airplanes should not exist (fix the /proc). Martin Rex had another solution -- allow fcntl() to remove read-only and append-only limitations, so that behaviour is at least explicit. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
